You need to call Yamaha and talk with their parts dept....you'll need the part number of your pedal...chances are they have the part or can get it ordered..I've attached a link below to the parts catalog...you may want to look the part number up first (before calling)..the link should be on "Pedals"...if you need help navigating through the catalog just let me know...

You can order direct from Yamaha, through their website. If you have trouble finding the correct part number, just send them an email and they'll help you out eventually. Sometimes you need to send repeated emails though. I've purchased quite a few spare parts direct.

You need to create an account first. Then once you're in, just search the part database using the model number. For example, if you enter DFP (for double foot pedal), you'll get a bunch of suggestions in a dropdown, then you can click on one of them, then click "GO" and you'll be presented with a diagram that shows all the individual parts and their numbers, along with a list of the parts, and the ability to add them to your shopping cart.

Keep in mind that the prices for parts are kind of high. For example, one of their bass drums beaters for the newest generation of their pedals is about $50. Other stuff is more reasonable.

Send an email. I was looking to buy a replacement drive shaft a while back, they had it listed for $300, but when I emailed them, they offered to sell it for $175. Still way too much, but you might be able to get a more reasonable price on the parts you need.